20 diarrheal samples from piglets of a pig farm were examined with PAGE, and 11 of them manifested the pararotavirus (group C) RNA electrophoretic profile. An acute watery diarrhea occurred after inoculating newborn colostrumdeprived piglets.Rotavirus (group A) ELISA and pararotavirus (group B) counter immunoelectrophoresis showed that the virus has no serologic relations with group A and B rotaviruses.